Not sure exactly how this would work but maybe you could run a seperate "dummy h2h league" with mostly same players and rig the last week to have the playoff teams aligned in the right spots. Don't know what the commish tools in yahoo are so maybe you could go back and bench/start certain players specific weeks to get the standings to work correctly.
Seems sort of unfair to the team leading the roto to have to go into a win or out situation, last year in 1 roto league we had 4 teams within 2 points of first on the final day of the year. It doesn't get much spicier than that
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